The present invention relates to switches of the type employed for switching fractional ampere current where it is desired to have a push-to-actuate type of operation. Switches of this type are desirable where low cost, compact size and minimal protrusion from a panel are desired.
Heretofore known low current switches have employed various techniques, one of which has been push-to-actuate switches which employ over-center or toggle spring mechanisms to move the contacts of the switch in response to user movement of the actuator. Such switches have proven to be widely used because of their positive making and breaking characteristics, but are relatively costly in high volume mass production because of the numerous discrete parts and costly noble metal contacts required for performing the switching operation and to minimize arcing upon breaking. Where fractional or subfractional ampere current is being switched, the need for noble metal or separate contacts for switching the current and preventing arcing is eliminated. Therefore, it has been desired to provide a simpler yet reliable and lower cost switch for low current switching element with fewer pans.
Heretofore, capacitance change type switching has been used for smooth panel switches where the user touches a laminant on the panel which effects a change in capacitance as between two plates which is then detected by appropriate circuitry and discerned as a switching operation. However, known capacitance switching has not provided for significant movement or tactilely discernible switching action to give positive feedback to the user that the switching has occurred. It has therefore been desired to provide a low current switching mechanism which is minimum in manufacturing cost and which provides the movement and tactilely discernible indication of movement similar to switching that of a mechanical contact type switch without the need for such contacts.